Anti-Inflammatory Effects, SAR, and Action Mechanism of Monoterpenoids from Radix Paeoniae Alba on LPS-Stimulated RAW 264.7 Cells.

Xiaoxu Bi,Peipei Guan,Yu Mu,Tiange Qu,Xiaodan Qu,Li Han,Xueshi Huang,Zhanyou Wang

doi:10.3390/molecules22050715

Abstract

Nine monoterpenoids from Radix Paeoniae Alba, including paeoniflorin derivatives, paeoniflorin (PF), 4-O-methylpaeoniflorin (MPF), 4-O-methylbenzoylpaeoniflorin (MBPF); paeonidanin derivatives, paeonidanin (PD), paeonidanin A (PDA), albiflorin derivatives, albiflorin (AF), benzoylalbiflorin (BAF), galloylalbiflorin (GAF), and debenzoylalbiflorin (DAF), were obtained in our previous phytochemistry investigations. Their anti-inflammatory effects were determined in the present study. The expression and production of pro-inflammatory cytokines in lipopolysaccharides (LPS)-stimulated RAW 264.7 cells were measured using an Elisa assay and nitric oxide (NO) release was determined using the Griess method. The results demonstrated that the most of the monoterpenoids suppressed the LPS-induced production of NO, interleukin-6 (IL-6), and tumor necrosis factor alpha (TNF-α). The anti-inflammatory activities of these monoterpenoids were closely related to their structural characteristics. Paeoniflorins and paeonidanins presented stronger anti-inflammatory activities than those of albiflorin derivatives. Furthermore, the action mechanisms of MBPF, having a strong anti-inflammatory effect, were investigated using quantitative reverse transcription polymerase chain reaction (RT-PCR) and Western blot methods. The results indicated that MBPF could down-regulate the mRNA and protein expression level of inducible nitric oxide synthase (iNOS) in LPS-stimulated RAW 264.7 cells. The mitogen-activated protein kinase (MAPK), phosphatidylinositol 3-kinase (PI3K)/AKT and nuclear factor κB (NF-κB) signaling pathways are involved in mediating the role of MBPF in suppressing the expression and production of pro-inflammatory cytokines in RAW 264.7 cells.

Highlights

Radix Paeoniae Alba, the dried rhizome of Paeonia lactiflora Pall., is a traditional Chinese medicine that has been used in a number of Asian countries for treatment of rheumatoid arthritis, to alleviate inflammation, amenorrhea, epistaxis, abdominal pain, and other symptoms [1,2,3]
MPF, paeonidanin A (PDA), PDA, GAF, and vitro,inwe measured the production of nitric oxide (NO), IL-6, and IL-6, TNF-α in LPS-stimulated
PDA, GAF, and DAF, The results showed paeoniflorin (PF, MPF, derivatives and MBPF) and and PDA)

Summary

Introduction

Radix Paeoniae Alba, the dried rhizome of Paeonia lactiflora Pall., is a traditional Chinese medicine that has been used in a number of Asian countries for treatment of rheumatoid arthritis, to alleviate inflammation, amenorrhea, epistaxis, abdominal pain, and other symptoms [1,2,3]. Thethe literature (LPS)-induced RAW 264.7 cells [10]. LPS binds the Tollwidely used for evaluating the anti-inflammatory effects of natural products [12]. LPS binds the like receptor and activates a set of intracellular signaling cascades, such assuch mitogen-activated protein. Toll-like receptor and activates a set of intracellular signaling cascades, as mitogen-activated kinase (MAPK), phosphatidylinositol. 3-kinase (PI3K)/AKT and the NF-κB signal pathways, to induce protein kinase (MAPK), phosphatidylinositol 3-kinase (PI3K)/AKT and the NF-κB signal pathways, the expression cytokines,of including factor-α (TNF-α), interleukin-1β and interleukin-6. In the interleukin-6 (IL-6), and of inflammatory enzymes, such as inducible nitric oxide synthase present study, anti-inflammatory assays ofanti-inflammatory nine isolated monoterpenoids wereisolated carried [13,14,15,16].comparative. The effects of monoterpenoids on Toll receptor signaling were investigated

Results and Discussion

Effects

Cell Culture and Cytotoxic Assay

Western Blot Analyses

Statistical Analyses

Conclusions